Material mixing and applying apparatus



Feb. 8, 1966 R. N. LEVAKE 3,233,530

MATERIAL MIXING AND APPLYING APPARATUS Filed Nov. 5, 1962 2 Sheets-Sheet 1 G 'BQ 8 78 86 RICHARD LEVAKE INVENTOR HUEBNER a WOR/PEL ATTORNEYS BY R. N. LEVAKE 3,233,580

MATERIAL MIXING AND APPLYING APPARATUS 2 Sheets-Sheet 2 Feb. 8, 1966 Filed NOV. 5, 1962 INVENTOR HUEBNER 8 WOR'REL A 7'7'ORNEYJ RICHARD LEVAKE United States Patent 3,233,580 MATERIAL MIXING AND APPLYENG APPARATUS Richard N. Levake, Phoenix, Ariz., assignor to Plastic Materials, Inc., a corporation of California Filed Nov. 5, 1962, Ser. No. 235,345 Claims. (Cl. 118-617) The present invention relates to a mixing and applying apparatus for surfiace coating materials and more particularly to a nozzle device having special advantage in the coating of the interior surfaces of hollow cylindrical articles with a mixed material while the material is in a plastic state. The invention features a nozzle device adapted to be rotated about the longitudinal axis of such an article thereby to mix a plurality of substances delivered in discrete proportions to the device and to apply by centrifugal force the resulting mixture to the interior surface of the article.

While the invention is susceptible to a wide range of utilization in mixing two or more substances, preferably of a type which will react with each other, and subsequently applying by centrifugal force the resulting mixture while it is in a plastic state thereby uniformly to coat the inner peripheral surface of a hollow cylindrical article, such as concrete pipe and the like, the more specific aspects of the invention embody apparatus adapted to utilize centrifugal force for thoroughly mixing a matrix substance with a suitable accelerator, or activating agent, to form a thermosetting plastic material and for so applying the mixed material. By utilizing a hollow cylindrical form, and by depositing a coating of substantial radial thickness, the invention has been utilized to fabricate pipe by a centrifugal deposition of the thermosetting plastic material.

Previously existing apparatus to effect mixing and applying of similar mixtures while in a plastic state were incapable of efiicient cyclic operation. Typical of such previous structures were those which admitted a pie-mixed thermosetting plastic material to a centrifugal applicator head. With any type of thermosetting plastic, such an applicator head must be cleaned within a short period of time following the termination of flow through the device. If not so cleaned, the plastic material cures and hardens within the applicator device and prevents further fiow therethrough at a subsequent time.

Certain of such prior art devices also utilize a mechanical agitator to which is supplied discrete proportions of a matrix material and an activating agent. The mechanical mixing apparatus is arranged to discharge the resulting mixture to a centrifugal applicator head for sub sequent application as a surface coating for the interior of hollow cylindrical articles. Depending upon the curing time, or pot-life, of such a mixture, this type of apparatus may be marginally adaptable for cyclic operation wherein a plurality of articles are successively coated. In any event, such apparatus must be disassembled and cleaned of all matrix material with which the activating agent has been mixed or the apparatus is rendered useless upon subsequent curing and hardening of the mixture.

Accordingly, it is an object of the present invention to provide a centrifugally operating and mixing nozzle which is well suited for cyclic operation in applying thermosetting plastic materials and the like.

Another object is to provide a mixing and applying nozzle device capable of mixing two or more substances delivered thereto in discrete proportions and of discharging =by centrifugal force the resulting mixture.

Another object is to provide a mixing and applying nozzle device which insures the discharge of all substances delivered to it for mixture and applying by centrifugal force.

Another object is to provide a centrifugally operated 3,233,580 Fatented Feb. 8, 1966 nozzle device adapted to intermix a matrix substance and an activating agent delivered to the device, both the mixing Within the device and the discharge therefrom being effected upon a tapered surface and under the influence of centrifugal force.

These, together with other objects, will become more fully apparent upon reference to the following description and accompanying drawings.

In the drawings:

"FIG. 1 is a view in side elevation of a mixing and applying nozzle device embodying the principles of the present invention sup-ported coaxia-lly within a cylindrical pipe, the supporting structure being shown in longitudinal section and certain components operably associated with the device being shown schematically.

FIG. 2 is an enlarged view in longitudinal, vertical section of the mixing and applying device taken on line 22 of FIG. 1.

FIG. 3 is a view similar to that of FIG. 2 except that the device is shown in an operating condition wherein a plurality of substances are being delivered to the device for mixing and subsequent application to the pipe, which is shown fragmentarily.

PIG. 4 is .a view of the nozzle device in end elevation taken from a position indicated by the line 44 in FIG. 2.

Referring specifically to FIG. 1, a hollow cylindrical article lit having an inner peripheral surface 11 which is to be coated by apparatus embodying the principles of the present invention is shown as being supported in a cradle 12. In commercial use of the invention, the hollow cylindrical article is frequently a concrete pipe, clay pipe, or pipe of other material to be coated providing a longitudinal axis 13.

A mixing and applying nozzle device is indicated generally at 15 and is shown as being supported for rotation about the axis 13 by means of a plurality of setscrews 16 connecting the device to a tubular shaft 17 of an air motor 18. The air motor serves as a source of rotary power and is supported at the distal end of a tubular boom 20 extended coaxially with the cylindrical article 10.

A frame 21 serves as a rigid support for the boom 20 and forms part of a mobile vehicle generally indicated at 22. The vehicle is arranged for reciprocal movement along a path parallel with the axis 13, and illustrates at 22. The vehicle is arranged for reciprocal movement between the mixing and applying nozzle device 15 and the hollow article 10. Such movement is desirable to achieve proper distribution of coating material to be applied to the inner peripheral surface ill. 'The boom 20 also provides a rigid support for a pair of axiallv spaced bearings 23 to permit rotation of the motor 18 about the axis 13 and relative to the boom 20. An air inlet conduit 24 is connected between the motor 18 and a tank 25 which constitutes a supply of air under pressure as the motive force to drive the motor 18. A valve 26 is provided in the conduit 24 selectively to control operation of the motor, and an exhaust conduit 27 is connected to the motor to carry air discharge therefrom.

Also supported within the boom is a first conduit 30 which is connected to the mixing and applying device 15 to supply a suitable activating agent from a tank 31. A valve 32 is provided in the conduit 30 to control flow of the activating agent to the mixing and applying device 15. A second conduit 33 is also supported in the boom and is connected between the device 15 and a tank 34 to supply a suitable matrix material. A valve 35 is provided in the conduit 33 to effect appropriate control of the flow of matrix material to the device 15. In one embodiment of the invention, commercially available polyester resins have been employed as satisfactory matrix materials, such resins being accelerated to effect thermosetting curing by commercially available peroxide accelerators appropriate for a given resin. With such a matrix material, the peroxide accelerator serves as the activating agent. Satisfactory coating of interior articles has been effected by utilizing a mixture of polyester resin and peroxide accelerator in relative proportions as small as three-hundred parts by volume of resin to one part of peroxide accelerator. In the event that curing time is to be lessened, the proportion of peroxide accelerator is increased. In addition, the matrix material may be in the form of such a polyester resin intimately mixed with particles of silica, the proportions being as great as one part of resin to one part of silica by volume.

A third conduit 46 is also supported in the boom 21 and connnects the mixing and applying device with a supply reservoir 41 for a bulk filler material, the use of which is optional. A flow control valve 42 is provided selectively to deliver such bulk material to the device 15 at a predetermined proportion. Cottonseed hulls and like cellulose material of low density and high bulk have been advantageously employed with the device 15. Other examples of suitable bulk filler materials are glass fibers, asbestos fibers, and other particles of low density inorganic substances.

Another example of a thermosetting plastic material which can be mixed and applied by the device 15 is a Portland cement mortar. The mortar is mixed from a matrix substance composed of sand and Portland cement in suitable proportions, as rich as equal parts by Weight, and supplied to the device through the hopper 34, valve 35, and conduit 33. With such a matrix substance, the activating agent supplied through conduit is water and in a suitable proportion to result in a wet plastic cement mortar upon mixing with the sand and Portland cement matrix substance.

By referring more particularly to FIGS. 2, 3 and 4, it can be seen that the mixing and applying nozzle 15 comprises an annular outer housing 45 carrying a collar 46 detachably secured to the motor shaft 17 by a plurality of circumferentially located setscrews 16. The housing 45 includes an annular outer wall 47 extended a predetermined axial distance. The Wall provides an inner peripheral surface 48 which is generated about the axis 13 and approximates a right circular cone. As shown in the drawings, the surface 48 tapers outwardly from the axis 13 and terminates in a discharge edge 49 circumscribin the axis and lying in a radial plane.

The device 15 also includes an inner housing 5 disposed coaxially with the outer housing 45 and having an annular wall 51 affording an inner peripheral surface 52. The surface 52 constitutes a mixing surface and is generated about the axis 13 to approximate a right circular cone. By substituting slightly curved lines for the generatrices of the right circular cones defined by the surfaces 48 and 52, it is possible to generate conoids which, without responding literally to the definition of a right circular cone, are functionally indistinguishable and regarded as equivalent. Consequently, an inclusive term embracing right circular cones and functionally similar analogues is used, The wall 51 is extended axially while tapering radially outwardly and terminates in a circumferential discharge station in the form of a plurality of ports 53 provided therein. A first end wall 54 is integrally joined to the annular wall 51 and is axially spaced from a second wall 55, in sealing relationship with the wall 51. The second wall 55 is provided with a plurality of circumferentially spaced discharge openings 56 in communication with a mixing chamber 57 formed by the annular wall 51 and the axially spaced end walls 54 and 55.

A third wall as is axially spaced from the second wall 55 and remote from the first wall 54 to form a flow chamber 61. The chambers 57 and 61 are both included within the inner housing 59. A central aperture is provided in the third wall and affords an annular surface 62 of a dimension to provide a running fit in substantial scaling engagement with the conduit 33. An annular washer 63 is disposed in circumscribing relationship to the conduit and in axial proximity to the third wall to provide additional sealing between the device 15 and the conduit 33. It should also be noted that the relative radial dimensions of the inner housing 5 and the annular outer housing 45 define an annular throat 64 in communication with the conduit 40.

A first check valve assembly is screw-threadably carried on the inner conduit 3t} and is provided with a plurality of discharge ports 71 at a first axial and radial location for the activating agent flowing from the tank 31. A central aperture in wall 55 permits rotation thereof relative to the valve assembly 7i) and is of a dimension to effect substantial sealing engagement therebetween. A second check valve 72 is disposed about the conduit 3t? to close the discharge opening of the conduit 33 by means of a biasing spring 73 carried on the valve assembly 70. Both of the check valves 76 and 72 are biased by respective springs pro-loaded at predetermined values, such pre-load being overcome during operation by the substance flowing through the conduit respectively associated with each valve.

A web is integrally radially extended from the wall 54 and is secured to the outer housing by a plurality of capscrews 76. The capscrews are extended through a plurality of circumferentially spaced, peripheral tabs '77 radially extended from the web 75. The tabs 77 in conjunction with the central portion of the web 75 and the outer housing 45 define a plurality of quadrantal discharge openings 78.

An auxiliary web 8 1 is provided with a plurality of uniformly spaced circumferential discharge openings 31 and is secured to the web 75 by a central capscrew S2. A plurality of axially extended capscrews 83 permit construction of the inner housing in separate components such as the second and third walls and maintain such walls in assembled relationship as shown in FIGS. 2 and 3. The auxiliary web 82 carries at its outer periphery an accelerating flange 34 affording an outwardly tapered surface 85, generated about the axis 13 and approximating a right circular cone. It should be noted that the surface 3S is tapered at a much steeper angle than either of the surfaces 48 or 52. An annular collar 86 receives the outer housing 45 to insure concentricity between the flange 84 and the housing as well as a circumferential discharge edge 87. The flange 84 is extended axially and radially a predetermined distance to effect, at a given rotational speed, acceleration of substances discharged onto the surface 35 through the openings 78 and 81.

Operation The operation of the described embodiment of the subject invention is believed to be readily apparent and is briefly summarized at this point. The mixing and applying nozzle device 15 may be utilized in applying various coatings of different matrix materials to various objects but is conveniently illustrated in its application of surface coating materials to hollow cylindrical articles. Depending upon the radial thickness of the coating to be applied, the surface texture desired, and the other characteristics which the coating is to possess, bulk material fed through conduit 41 from the supply 41 is optionally employed. In the event any suitable bulk material is employed in the resulting mixture, such material is ideally delivered to the device 15 by a pneumatic conveying system so that discrete particles pass through the throat 64 and are urged into contact with the surface 48. The conveying air is then discharged axially through a plurality of openings 83 provided in the webs 75 and 80 at a radial distance from the axis 13 less than that of the discharge openings 81.

Under normal circumstances in coating hollow articles such as concrete pipe, the device 15 is utilized in coating Y the interior surface with a plastic material, such as that resulting from a mixture of polyester resin and peroxide accelerator within the range of proportions described above. Such coatings have been applied in radial thicknesses ranging from one-thousandth of an inch to more than one-eighth of an inch; with the addition of a cellulose bulk material, such as cottonseed hulls, coatings of a radial thickness in excess of one inch have been applied.

The matrix material is delivered to the device from the supply tank 34 through valve 35 and conduit 33 at a'pressure sufficient to overcome the pre-load force of the spring 73 urging the check valve 72 in closing engagement with the discharge opening of the conduit. :The activating agent is supplied to the device 13 through conduit leading from the supply tank 31 .and controlled by the valve 32. The volumetric proportions of the matrix material and activating agent are ideally controlled through any suitable interlock and proportioning device connecting the valves 32 and 35 and indicated schematically at 90.

Initial discharge of the matrix material from the conduit 33 past the annular valve is directed into the flow chamber 61 formed by the third wall 60 and second wall 55. The flow of matrix material then proceeds through discharge openings 56 into the mixing chamber 57. Simultaneously, the activating agent is discharged from conduit 30 through the check valve assembly 79 and into the mixing chamber 57. As the activating agent flows from the discharge port 71 of the check valve 70, it is deposited upon the tapered surface 52. It should be notedthat the device 15 is concurrently rotated about the axis 13 at a speed sufficient to effect intimate intermixing of the matrix material and the activating agent. In a commercial embodiment of the device 15 employed to coat concrete pipe of a diameter of twelve inches, the motor 18 is driven at a rotational speed of 8,000 rpm. Satisfactory results have been obtained through operation of the motor in a range of 3,600 to 15,000 r.p.m. When rotated at such speeds, centrifugal force acting .upon the matrix material and activating agent cause movement of such mixed materials radially outwardly along the surface 52 to be discharged from the circumferential discharge ports 53. The mixture is deposited upon the tapered surface 48 of the outer housing land is further subjected to centrifugal force to urge the mixture radially outwardly and axially along the surface 48 toward the discharge edge 49. During such progressive radial and axial movement, a further intimate interfmixing of the matrix material and the activating agent is effected. In the case of polyester resin, such uniform intimate intermixing is an absolute essential to provide a continuity of surface coating upon the interior 11 and to prevent any holiday or surface discontinuity in such coating. The position of the valves 7'0 and '72 and the general direction of movement of the matrix material and activating agent as well as the resulting mixture during mixing and applying operations of the device 15 is indicated by the arrows in FIG. 3.

During rotation of the device 15 which results in the mixing and applying of the thermosetting material through the action of centrifugal force, the mobile vehicle 2.2 is reciprocated along a path parallel to the axis 13. Such reciprocal movement is continued and successive layers of material are deposited until the desired radial thickness of coating has been effected. Upon achieving the desired thickness, the flow control valves 32 and 35, as well as valve 42 in. the event a bulk filler material is being employed, are closed. Upon closure of the flow control valves, the check valves 70 and 72 move to the closed posItiou while rotation of the mixing and applying device 15 is continued. Centrifugal force acting upon any residual materials inthe flow chamber 61 and the mixing chamber 57 is effective to intermix residual materials and to discharge the mixture along the surface 48 and from the edge 49. The accelerator flange 84 operates to impart a higher peripheral speed to the mixture. The flange is formed at a radial dimension to effect the desired peripheral speed at the discharge edge 87, the dimension being selected to suit the particular viscosity and specific gravity of the mixture.

Upon completion of the coating of one hollow article it), the device 15 is with-drawn and successive articles may be deposited upon the cradle 12. The above cycle of coating deposition is repeated upon successive articles, as desired.

Accordingly, a mixing and applying nozzle is provided by the present invention which effectively intermixes by centrifugal force a matrix substance and a suitable activating agent and deposits the resulting mixture upon a target surface such as the interior surface of a hollow article. The device is ideally suited for cyclic operations and operates effectively following intermittent periods of non-use. Such cyclic operation and aperiodic use is permitted due to the fact that the device mixes the matrix material with the activating agent immediately before discharge and insures discharge of all mixed material from the nozzle. In addition, the nozzle is capable of adding a bulk filler material to the mixture. The bulk filler material is added subsequent to the addition of the activating agent to the matrix substance which insures intimate intermixing thereof to effect satisfactory curing of the resulting mixture.

. Although the invention has been herein shown and described in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of the invention, which is not to be limited to the details dis- V closed herein but is to be accorded the full scope of the claims so as to embrace any and all equivalent devices and apparatus.

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

' 1. In a material mixing and applying nozzle, the combination of an inner wall providing an internal substantially conical surface, the larger end of said inner wall having discharge passage means, an outer wall providing an internal substantially conical surface having an enlarged end providing a circumscribing discharge edge, powered means mounting said Walls for rotation about a common axis concentric to said surfaces with the inner surface of the outer wall radially spaced from and overlying the discharge passage mcans of the first wall, means including first and second conduits for separately delivering first and second materials, respectively, to the inner surface of the inner wall for mixing and centrifugal discharge from the discharge passage means thereof onto the inner surface of the outer wall, and means including a third conduit for delivering a third material exteriorly of the inner wall to the inner surface of the outer wall for mixing with the first and second materials and centrifugal discharge from the discharge edge thereof.

2. A mixing and applying nozzle comprising an outer wall symmetrical about a predetermined axis, powered means connected to the outer wall for rotating it about said axis, an inner wall within the outer wall and rotated therewith providing an internal substantially conical first surface concentric to said axis, the larger end of said inner wall having discharge passage means, the outer wall circumscribing the inner wall and providing an internalsubstantially conical second surface concentric to said axis and radially spaced from the discharge passage means of the inner wall and having an enlarged end circumscribed by a discharge edge, means including first and second conduits for separately delivering first and second materials, respectively, to the first surface for mixing and centrifugal discharge from the discharge passage means thereof onto the second surface, and means including a third conduit for delivering a third material exteriorly of the inner wall to the second surface for mixing with the first and second materials and centrifugal discharge from the discharge edge of the second surface.

3. In apparatus adapted to deposit a material in a plastic state on the inner peripheral surface of a hollow cylindrical article and having rotary power means and supply means to provide in predetermined discrete proportions a matrix material and an activating agent therefor, a mixing and applying nozzle device comprising an annular outer wall; means connecting the outer wall to said power means and supporting it for rotation about an axis substantially coincident with the longitudinal axis of said article, the outer wall affording an inner peripheral surface generated about said axis and extended therealong a predetermined linear distance at progressively increasing increments of radial displacement therefrom to provide an outwardly flaring mixing and accelerating surface, said outer wall terminating in a circumferential edge disposed at a predetermined radius from said axis; means including a first check valve disposed within the outer Wall and communicating with said supply means selectively to discharge said activating agent at a first axial location for deposition on said inner peripheral surface; means including a second check valve disposed within said outer wall adjacent to said first check valve at a second axial location to discharge said matrix material for deposition on the inner peripheral surface; whereby the matrix material and activating agent deposited on said inner peripheral surface are intimately intermixed and accelerated circumferentially by said inner peripheral surface until centrifugal force acting upon said intermixed material and agent effects progressive movement outwardly along said surface to be discharged from said circumferential wall edge.

4. In apparatus adapted to deposit a material in a plastic state on the inner peripheral surface of a hollow cylindrical article and having rotary power means and supply means to provide in predetermined discrete proportions a matrix substance and an activating agent therefor, a mixing and applying nozzle device comprising an annular outer wall; means connecting the wall to said power means and supporting it for rotation about an axis substantially coincident with the longitudinal axis of said article; the outer Wall affording an inner peripheral surface generated about said axis and extended therealong a predetermined linear distance at progressively increasing increments of radial displacement therefrom to provide a first outwardly flaring mixing and accelerating surface, said wall terminating in a circumferential discharge edge lying in a radial plane and spaced at a predetermined radius from said axis; an annular inner wall radially spaced from said outer wall and affording an inner peripheral surface generated about said axis and extended therealong a predetermined linear distance at progressively increasing increments of radial displacement therefrom to provide a second outwardly tapering mixing and accelerating surface, said inner wall being provided with circumferentially extended peripheral discharge ports to permit centrifugal discharge therefrom onto the inner peripheral surface of said outer Wall during rotation of the device; means including a first check valve disposed within the inner wall and communicating with said supply means selectively to discharge said activating agent at a first axial location for deposition on the inner peripheral surface of said inner wall; means including a second check valve and com municating with said supply means to discharge said matrix material at a second axial location for deposition on the inner peripheral surface of said inner wall; and means interconnecting said inner and outer walls.

5. The apparatus of claim 4 wherein said first and second check valves are spaced axially of each other.

6. The apparatus of claim 4 wherein the respective inner peripheral surfaces of said inner and outer walls are surfaces of revolution at least approximating respective right circular cones.

7. In apparatus adapted to deposit a material in a plastic state on the inner peripheral surface of a hollow cylindrical article and having rotary power means and supply means to provide in predetermined discrete proportions a matrix substance and an activating agent therefor, a mixing and applying nozzle device comprising an annular outer wall; means connecting the wall to said power means and supporting it for rotation about an axis substantially coincident with the longitudinal axis of said article; the outer wall affording an inner peripheral surface generated about said axis and extended therealong a predetermined linear distance at progressively increasing increments of radial displacement therefrom to provide an outwardly flaring first mixing and accelerating surface, said wall terminating in a circumferential discharge edge lying in a radial plane and spaced at a predetermined radius from said axis; an annular inner wall radially spaced from said outer wall and affording an inner peripheral surface generated about said axis and extending therealong a pre determined linear distance at progressively increasing increments of radial displacement therefrom to provide an outwardly tapering second mixing and accelerating surface, said inner wall being provided with circumferentially extended peripheral discharge ports to permit centrifugal discharge therefrom onto the inner peripheral surface of said outer wall during rotation of the device; means including a first check valve disposed within the inner wall and communicating with said supply means selectively to discharge said activating agent at a first axial locationfor deposition on the inner peripheral surface of said inner wall; means including a second check valve and communicating with said supply means to discharge said matrix material at a second axial location for deposition on the inner peripheral surface of said inner wall; axially spaced, radially extended end walls cooperating with said inner wall except for said discharge station to form a mixing chamber for said matrix material and activating agent; and means interconnecting said inner and outer walls.

8. In apparatus adapted to deposit a mixed material in a plastic state on the inner peripheral surface of a hollow cylindrical article and having rotary power means and supply means to provide in predetermined discrete proportions a matrix substance and an activating agent therefor, a mixing and applying nozzle device comprising an annular outer wall; means connecting the wall to said power means and supporting it for rotation about an axis substantially coincident with the longitudinal axis of said article; the outer wall affording an inner peripheral surface generated about said axis and extended therealong a predetermined linear distance at progressively increasing increments of radial displacement therefrom to provide an outwardly flaring first mixing and accelerating surface, said wall terminating in a circumferential discharge edge lying in a radial plane and spaced in a predetermined radius from said axis; an annular inner Wall radially spaced from said outer wall and affording an inner peripheral surface generated about said axis and extended therealong a predetermined linear distance at progressively increasing increments of radial displacement therefrom to provide an outwardly tapered second mixing and accelerating surface, said inner wall being provided with circumferentially extended peripheral discharge ports to permit centrifugal discharge therefrom onto the inner peripheral surface of said outer wall during rotation of the device; means including a first check valve disposed within the inner housing and communicating with said supply means selectively to discharge said activating agent at a first axial location for deposition on the inner peripheral surface of said inner wall; means including a second check valve and communicating with said supply means to discharge said matrix material at a second axial location for deposition on the inner peripheral surface of said inner wall; axially spaced, radially extended end walls on said inner wall, a perforate web radially extended from one of said end walls and provided with circumferentially spaced peripheral discharge openings adjacent to said outer wall; and means connecting said web with said outer wall.

9. The apparatus of claim 9 wherein a peripheral accelerator flange is secured to said outer wall to receive the intermixed material from said peripheral discharge openings in said web, said flange being extended a pre determined radial distance to accelerate material discharged thereon during rotation of said wall and terminating in a circumferential discharge edge lying in a radial plane.

10. In apparatus adapted to deposit a mixed material in a plastic state on the inner peripheral surface of a hollow cylindrical article and having rotary power means, supply means to provide in predetermined discrete proportions a matrix substance and an activating agent therefor, said supply means including first and second concentric tubular conduits terminating in discharge ends at respective axial locations, and provided with respective discharge openings, and separate supply means for discrete particles of bulk filler material, said separate supply means including a third tubular conduit concentric with said first and second conduits, a mixing and applying nozzle device comprising an annular outer wall, means connecting the wall to said power means and supporting the wall for rotation about an axis substantially coincident with the longitudinal axis of said article; the outer wall aifording an inner peripheral surface of revolution at least approximating a right circular cone to provide an outwardly flaring first mixing and accelerating surface; an inner annular wall radially spaced from said outer wall and alfording an inner peripheral surface of revolution at least approximating a right circular cone to provide an outwardly tapered second mixing and accelerating surface; axially spaced, radially extended end walls on said inner housing to form a mixing chamber, the inner wall being provided with a plurality of circumferentially spaced discharge ports at the maximum radial dimensions of said wall, the relative positions of said inner wall and said outer wall defining an annular throat within said outer wall; means connecting the outer wall to said third conduit to provide communication between said conduit and said throat; one of the end walls adjacent said discharge ports of said annular wall being provided with a central aperture to receive the innermost conduit; a third radial wall secured to said inner wall and axially spaced from aforesaid end wall to form a flow chamber adjacent to said mixing chamber, said third wall being provided with a central aperture to receive the outer conduit of said first and second conduits in sealing relationship and to permit relative rotation therebetween, aforesaid end wall provided with a plurality of circum ferential discharge vents communicating said mixing chamber with said flow chamber; check valve means carried at the discharge ends of each of the first and second conduits; a perforate web radially extended from said inner wall; and means interconnecting the web with said outer wall.

References Cited by the Examiner UNITED STATES PATENTS 2,431,658 11/1947 Demb et a1. 118-317 2,794,679 6/1957 Jauch et al. 239-215 2,967,667 1/1961 Norris 118626 X 3,011,472 12/1961 Kent et al 117-93.42 X 3,029,027 4/1962 Gray 118-306 X DANIEL BLUM, Primary Examiner.

RICHARD D. NEVIUS, Examiner. 

1. IN A MATERIAL MIXING AND APPLYING NOZZLE, THE COMBINATION OF AN INNER WALL PROVIDING AN INTERNAL SUNSTANTIALLY CONICAL SURFACE, THE LARGER END OF SAID INNER WALL HAVING DISCHARGE PASSAGE MEANS, AN OUTER WALL PROVIDING AN INTERNAL SUBSTANTIALLY CONICAL SURFACE HAVING AN ENLARGED END PROVIDING A CIRCUMSCRIBING DISCHARGE EDGE, POWERED MEANS MOUNTING SAID WALLS FOR ROTATION ABOUT A COMMON AXIS CONCENTRIC TO SAID SURFACES WITH THE INNER SURFACE OF THE OUTER WALL RADIALLY SPACED FROM AND OVERLYING THE DISCHARGE PASSAGE MEANS OF THE FIRST WALL, MEANS INCLUDING FIRST AND SECOND CONDUITS FOR SEPARATELY DELIVERING FIRST AND SECOND MATERIALS, RESPECTIVELY, TO THE INNER SURFACE OF THE INNER WALL FOR MIXING AND CENTRIFUGAL DISCHARGE FROM THE DISCHARGE PASSAGE MEANS THEREOF ONTO THE INNER SURFACE OF THE OUTER WALL, AND MEANS INCLUDING A THIRD CONDUIT FOR DELIVERING A THIRD MATERIAL EXTERIORLY OF THE INNER WALL TO THE INNER SURFACE OF THE OUTER WALL FOR MIXING WITH THE FIRST AND SECOND MATERIALS AND CENTRIFUGAL DISCHARGE FROM THE DISCHARGE EDGE THEREOF. 